U.S. patent application number 11/173715 was filed with the patent office on 2006-06-15 for dipole antenna.
This patent application is currently assigned to HON HAI PRECISION IND. CO., LTD.. Invention is credited to Chen-Ta Hung, Wen-Fong Su, Lung-Sheng Tai.
Application Number | 20060125697 11/173715 |
Document ID | / |
Family ID | 36583173 |
Filed Date | 2006-06-15 |
United States Patent
Application |
20060125697 |
Kind Code |
A1 |
Hung; Chen-Ta ; et
al. |
June 15, 2006 |
Dipole antenna
Abstract
A dipole antenna (1) includes a first radiating trace (21) and a
first grounding trace (31) respectively extending in substantially
opposite directions, a second radiating trace (22) extending from
an end of the first radiating trace in a direction which
substantially perpendicular to the first radiating trace, and a
second grounding trace (32) extending from an end of the first
grounding trace in an opposite direction to the second radiating
trace. The total length of the first and second radiating traces
are 1/4 operating wavelength of the dipole antenna.
Inventors: |
Hung; Chen-Ta; (Santa Clara,
CA) ; Su; Wen-Fong; (Tu-Chen, TW) ; Tai;
Lung-Sheng; (Tu-Chen, TW) |
Correspondence
Address: |
WEI TE CHUNG;FOXCONN INTERNATIONAL, INC.
1650 MEMOREX DRIVE
SANTA CLARA
CA
95050
US
|
Assignee: |
HON HAI PRECISION IND. CO.,
LTD.
|
Family ID: |
36583173 |
Appl. No.: |
11/173715 |
Filed: |
June 30, 2005 |
Current U.S.
Class: |
343/700MS ;
343/795 |
Current CPC
Class: |
H01Q 1/38 20130101; H01Q
9/28 20130101; H01Q 1/2266 20130101 |
Class at
Publication: |
343/700.0MS ;
343/795 |
International
Class: |
H01Q 1/38 20060101
H01Q001/38; H01Q 9/28 20060101 H01Q009/28 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 10, 2004 |
CN |
200410066198.X |
Claims
1. A dipole antenna comprising: a first radiating trace extending
in a first direction; a first grounding trace aligned with the
first radiating trace; a second radiating trace extending in a
second direction from the first radiating trace; a second grounding
trace extending from the first grounding trace opposite to and
parallel to the second radiating trace; and a coaxial cable;
wherein the total length of the first and second radiating traces
are 1/4 operating wavelength of the dipole antenna.
2. The dipole antenna as claimed in claim 1, further comprising a
substrate on which the first and second radiating traces and the
first and second grounding traces are all disposed.
3. The dipole antenna as claimed in claim 2, further comprising a
pair of parallel matching traces disposed on the substrate and
connecting to the first radiating trace and first grounding trace
respectively.
4. A dipole antenna comprising: a pair of matching traces parallel
to each other with a predetermined distance; a first radiating
trace and a first grounding trace oppositely extending from ends of
the matching traces and aligned in a line; a second radiating trace
extending from around an end of the first radiating trace in a
first direction; a second grounding trace extending from an end of
the second radiating trace in a second direction which is opposite
to the first direction; wherein the second radiating trace is
parallel to second grounding trace.
5. The dipole antenna as claimed in claim 4, wherein the first
radiating trace is perpendicular to the second radiating trace.
6. The dipole antenna as claimed in claim 4, wherein one patch
trace, the first radiating trace and the second radiating trace
commonly constitute a U-like configuration, while the other patch
trace, the first grounding trace and the second grounding trace
commonly constitute a Z-like configuration.
7. The dipole antenna as claimed in claim 6, further including a
cable having outer and inner conductors respectively connected two
free ends of said pair of patch traces.
8. The dipole antenna as claimed in claim 5, further comprising a
substrate where the first and second radiating traces, the first
and second grounding traces and the matching traces are disposed
thereon.
9. An antenna comprising: a substrate; a pair of dipole elements
both disposed on the substrate and substantially having the same
length; said pair of dipole elements comprising a first pair of
dipole branches providing horizontal polarization, a second dipole
branches providing perpendicular polarization.
10. The antenna as claimed in claim 9, further including a pair of
matching traces providing impendence match adjustment between the
dipole antenna and a coaxial cable.
11. The antenna as claimed in claim 10, wherein the pair of
matching traces are substantially perpendicular to the pair of
first dipole branches and parallel to the pair of second dipole
branches.
12. The antenna as claimed in claim 11, wherein the pair of
matching traces are parallel to each other.
13. The antenna as claimed in claim 10, wherein the fist dipole
branches are aligned with each other while the pair of second
dipole branches are parallel to each other.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an antenna, and in
particular to a dipole antenna employed in a laptop computer, a
portable electronic device or other electronic devices.
[0003] 2. Description of the Prior Art or Related Art
[0004] When wireless communication technologies, such as WLAN
standards, are applied in electronic devices such as notebook
computers or portable game devices, antennas become indispensable
components to these devices for wireless access. As a basic antenna
structure, a dipole antenna is a popular choice for the RF engineer
because it has features of low cost and is easy to design and test.
A traditional dipole antenna usually includes a pair of linear
dipole elements extending in opposite directions, which can get
polarization in a single direction. But if the traditional dipole
antenna is assembled in a Liquid Crystal Display (LCD) of a
notebook or other portable devices, the receiving and transmitting
capability of the dipole antenna could be better when the LCD is in
a predetermined position (such as parallel to the ground), but also
could be worse when the LCD is in a different position (such as
perpendicular to the ground). So the open angle of the LCD relative
to a panel of the notebook computer will affect performance of the
dipole antenna or other single-liner polarized antenna assembled in
the LCD.
[0005] U.S. Pat. Publication No. 20040012534 discloses a dual-band
printed dipole antenna. The dipole antenna comprises a pair of
dipole elements (212, 222) operated in a lower frequency and
disposed on a substrate. The dipole antenna is formed into
inverted-V shape to for impendence matching purpose. However
vertical and horizontal polarization improvements are not
considered simultaneously in this design.
[0006] Hence, an improved dipole antenna is desired to overcome the
above-mentioned disadvantages of the prior and related arts.
BRIEF SUMMARY OF THE INVENTION
[0007] A primary object of the present invention is to provide a
dipole antenna having balanced polarization in both vertical
direction and horizontal directions.
[0008] A dipole antenna in accordance with the present invention
includes a first radiating trace and a first grounding trace
respectively extending in substantially opposite directions, a
second radiating trace extending from an end of the first radiating
trace in a direction which substantially perpendicular to the first
radiating trace, and a second grounding trace extending from an end
of the first grounding trace in an opposite direction to the second
radiating trace. The total length of the first and second radiating
traces are 1/4 operating wavelength of the dipole antenna.
[0009] Still another objects, advantages and novel features of the
invention will become more apparent from the following detailed
description of a preferred embodiment when taken in conjunction
with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a top plan view of a dipole antenna in accordance
with the present invention, which is disposed on a substrate;
[0011] FIG. 2 is a test chart recording for the dipole antenna of
FIG. 1, showing Voltage Standing Wave Ratio (VSWR) as a function of
frequency;
[0012] FIG. 3 is a recording of a horizontally polarized principle
plane radiation pattern in X-Y plane of the dipole antenna of FIG.
1 operating at a frequency of 2.45 GHz;
[0013] FIG. 4 is a recording of a vertically polarized principle
plane radiation pattern in X-Y plane of the dipole antenna of FIG.
1 operating at a frequency of 2.45 GHz;
[0014] FIG. 5 is a recording of a horizontally polarized principle
plane radiation pattern in X-Z plane of the dipole antenna of FIG.
1 operating at a frequency of 2.45 GHz;
[0015] FIG. 6 is a recording of a vertically polarized principle
plane radiation pattern in X-Z plane of the dipole antenna of FIG.
1 operating at a frequency of 2.45 GHz;
[0016] FIG. 7 is a recording of a horizontally polarized principle
plane radiation pattern in Y-Z plane of the dipole antenna of FIG.
1 operating at a frequency of 2.45 GHz; and
[0017] FIG. 8 is a recording of a vertically polarized principle
plane radiation pattern in Y-Z plane of the dipole antenna of FIG.
1 operating at a frequency of 2.45 GHz.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Reference will now be made in detail to a preferred
embodiment of the present invention.
[0019] Referring to FIG. 1, a dipole antenna 1 in accordance with
the present invention comprises a substrate 10, a radiating dipole
element 2 and a grounding dipole element 3, impendence matching
member 4 and a coaxial cable 5.
[0020] With reference to the definition of directions X, Y, Z in
FIG. 1, the radiating dipole element 2 is L-shaped and includes a
first radiating trace 21 that extends in a vertical direction
parallel to direction Z and a second radiating trace 22
perpendicularly extending from an end of the first radiating trace
21 and parallel to direction X. The first and second radiating
traces 21, 22 are also substantially perpendicular to each other.
The grounding dipole element 3 has the same dimension as that of
the radiating dipole element 2. The grounding dipole element 3
includes a first grounding trace 31 and a second grounding trace 32
extending from an end of the first grounding trace 31. The first
and second grounding traces 31, 32 are substantially perpendicular
to each other. The first grounding trace 31 extends oppositely to
the first radiating trace 21 and is aligned in a line with the
first radiating trace 21. The second grounding trace 32 is parallel
to the second radiating trace 22 but extends in an opposite
direction.
[0021] The impendence matching member 4 includes a pair of parallel
matching traces 41, 42 perpendicularly extending form ends of the
first radiating trace 21 and the first grounding trace 31,
respectively. The matching traces 41, 42 are substantially parallel
to each other and have the same dimension. The distance between the
matching traces 41, 42 and the length of the matching traces 41, 42
provide convenient adjustment for the impendence matching between
the dipole antenna 1 and the coaxial cable 5. The coaxial cable 5
includes an inner conductor 51 connecting with an end of one
matching trace 41 and an outer conductor 52 connecting with an end
of the other matching trace 42.
[0022] The first radiating trace 21 and the first grounding trace
31 can be treated as a first pair of dipole branches, which provide
horizontal polarization improvement on XY, YZ and XZ planes in FIG.
1. The second radiating trace 22 and the second grounding trace 32
can be treated as a second pair of dipole branches, which provide
perpendicular polarization improvement on each plane described
above. In this embodiment, the length of the first and second
radiating traces 21, 22 and the first and second grounding trace
31, 32 are both selected form a scope of 1/12 to 1/6 of operating
wavelength of the dipole antenna. The total length of the first and
second radiating traces 22 are 1/4 of operating wavelength, so do
the first and second grounding traces 32. In such a condition, a
balanced polarization on each plane is achieved, which are directly
shown on FIG. 3 to FIG. 8 with no obvious radiating blind area. The
impendence-matching problem will be solved by adjusting the length
of the matching traces 41, 42 and the distance therebetween. The
dipole elements 2, 3 and the matching traces 41, 42 are all
disposed on the substrate 10, which achieves an impact design and
need not to provide a complex impendence member. FIG. 2 shows a
test chart recording of Voltage Standing Wave Ratio (VSWR) of the
dipole antenna 1 as a function of frequency. Note that VSWR drops
below the desirable maximum value "2" in the 2.4-2.5 GHz frequency
band, indicating acceptably efficient operation in this frequency
band, which covers more than the total bandwidth of 802.1 lb
standard.
[0023] Since the dipole antenna 1 has a balanced polarization, when
it is assembled in a display of a notebook or other like portable
device, the dipole antenna 1 can provide desired transmitting and
receiving performance regardless what angle of the display
(relative to a panel of the notebook) is. Assembled with such
balanced polarization antenna, a user may enjoy good wireless
communication and need not to adjust the angle of the antenna, the
position of his portable device or open angle of the display.
[0024] It is to be understood, however, that even though numerous
characteristics and advantages of the present invention have been
set forth in the foregoing description, together with details of
the structure and function of the invention, the disclosure is
illustrative only, and changes may be made in detail, especially in
matters of shape, size, and arrangement of parts within the
principles of the invention to the full extent indicated by the
broad general meaning of the terms in which the appended claims are
expressed.
* * * * *